Flaming Sunup Sky
Flaming Sunup Sky (#18A8EB) is a true cyan with a vibrant character. It holds its own as a focal accent, carrying visual weight without tipping into neon territory. Its HSL profile (199°, 84%, 51%) places it in the highly saturated band at a mid lightness. Best used in small doses, like logos, CTAs, focus rings, or highlight text, where its saturation becomes a feature rather than noise. For a confident two-color system, pair it with its complementary orange. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Old French flamme, flame — present-participle of flame. As a color modifier, flaming implies a saturated-and-fire-and-bright-color quality, the bright color of autumn-Maple-and-Oak deciduous-foliage fall-color and Yule-log fire emission. Sits at the bright-and-warm end of the grid, parallel to fiery and blazing in usage.
English compound sun + up, sun-up. As a color modifier, sunup implies a first-light-and-eastern-horizon quality, the visual register of clear-sky eastern-horizon sunrise-and-first-light Rayleigh-scattered atmospheric Belt-of-Venus pink-and-orange surfaces under sunrise eastern-horizon light. Sits at the modifier-and-time end of the grid, parallel to rise and wake in usage.
The blue of a clear sky at noon — produced by Rayleigh scattering, the preferential dispersion of shorter wavelengths through atmospheric molecules. Air itself is colorless; the color we see is sunlight scattered toward our eyes by every cubic kilometer above. The reference shade is mid-latitude noon under a high pressure system: a clean, slightly green-shifted blue with the luminous depth of light scattered across an entire hemisphere of air.
Closest matches
The nearest named color in three reference sources, ranked by perceptual distance (ΔE76 in CIELAB). ΔE < 1 is imperceptible to most viewers; ΔE > 10 is clearly different. When two sources point to the same hex they’re merged into one tile; click any to open that color’s page.
Variations
Click any swatch to exploreHarmonies
Accessibility
How this color appears to viewers with the four major color-vision-deficiency types. Computed via the Machado (2009) physiologically-based model. If a tile matches the original, the color reads the same to that viewer.
The color used as foreground text against pure white and pure black, with the contrast ratio and WCAG 2.1 grade. Aim for AA (4.5:1) for body text and AA Large (3:1) for 18 pt+ headlines; AAA (7:1) is the gold standard for long-form reading surfaces.